Mercedes executive director Toto Wolff has claimed that Fernando Alonso is the team's number one target if they fail to agree a new deal with Lewis Hamilton.
Formula 1 champion Hamilton is yet to agree a new contract with Mercedes, despite reports that he has opened talks over a new three-year £70m deal.
"There's no hurry, we'll discuss it during the year," Wolff told Gazetta dello Sport.
"I'm an optimist. The priority is to continue with these drivers [Hamilton and Nico Rosberg]. Should it not be possible, then Alonso represents the first alternative, then there's Valtteri Bottas."
Alonso has rejoined McLaren for 2015, despite leaving them in 2007 just one season into a three-year contract.
